Damp Course Above Floor Level

Dpc material for cavity walls.

Damp course above floor level.

Historically damp proof courses may have been formed using bitumen slates lead pitch asphalt or low absorption bricks. Houses are usually built with a damp proof course dpc just above floor level to prevent moisture rising up but if this has failed or the property did not have a. Damp below damp proof course level. Selection of materials for damp proof course in buildings.

Damp proofing is defined by the american society for testing and materials astm as a material that resists the passage of water with no hydrostatic pressure. The external ground level must be 150mm below the damp course building reg the reason being that when rain fall hits the floor it will bounce up thus bypassing the dpc if it was level with the outside. Waterproof is defined by the astm as a treatment that resists the passage of water under pressure. External wall damp course is at door floor level.

A reason that building regs dictate the 150mm below dpc rule is to reduce any rain splashing above the dpc level where there is most risk of damp bridging to inside. A typical polymer damp proof course there are a number of alternatives to the modern dpc on a roll and these are sometimes found on older properties particularly those built prior to the second world war. Generally damp proofing keeps moisture out of a building where vapor barriers keep interior moisture from getting into walls. A quick summary checklist.

The plastic in the brickwork are weep holes. The third cause of damp is rising damp where moisture in the earth soaks through the foundations and walls of a house rising up through the layers or brick and causing damage. As it dries out the damp retreats slowly back to the points of ingress so if you are not able to see any isolated damp areas either ventilate and heat or shut all the doors and windows and use a dehumidifier. Tip 1 if a concrete floor is damp all over it is hard to isolate the moisture source.

Ground level damp proof courses have been mandatory in all british buildings since the public health act of 1875. Dpc above ground level. Dpc material for floors roofs etc. Types of materials for damp proof course.